HELP reading oscilloscope diagram

[Atlaπtis]

Homework Statement

I have to answer questions 1 - estimate the size (in volts) of the DC signal from CH1
and 2-estimate the peak-to-peak voltage AC signal of CH2, then find it's period and frequency
And then I'm supposed to 'briefly describe a simple example in which oscillations or waves with two or more frequencies are combined"
I don't know how to work out 1 and 2 from the diagram, I don't understand the scaling of the side to work out where each of them is.
And with the briefly describe part, is that just referring to how when you put two waves together with different frequencies, the amplitudes of each of them are added together to form a new wave-like shape?

http://i244.photobucket.com/albums/gg26/ValaRayne/IMG-1.jpg

 

[vk6kro]

I can't read the figures on your diagram, but maybe you can practice on this one:

http://dl.dropbox.com/u/4222062/Oscilloscope%20screen.PNG

If you know the vertical sensitivity is as shown, 0.2 volts per division, can you see that this waveform would have an amplitude of about 0.56 volts? (ie -0.28 to +0.28.)
This is the peak to peak voltage.

On the horizontal scale, each division is 10 microseconds (uS).
One full wave of the sinewave input occupies from 8 to 113 uS, so the period is 113 - 8 or 105 uS.
This means the waveform has a frequency of 1000000 / 105 or 9523 Hz.